It basically means you have the octatrack set up incorrectly. At least that's what happened with me. If I remember correctly the RM1x was sending midi timecode (which I believe spark does not support??) and spark's sequencer was getting stuck at the 4th step.

You'll need to verify in the manual and set up your octatrack corresponding to the settings supported. I believe it worked for me when I sent midi clock from my RM1x and received midi clock in and set midi clock start / stop in to be from the rm1x. Make sure your octatrack is sending midi clock out as well.

Mostly I think it was due to the midi timecode. Hope this helps you track it down.